The invention relates to a web feed section consisting of a bottom roll and a top roll which are adjustable with respect to their contact pressure by means of an actuator.
Feed sections of this type are used in paper- and boxboard-processing machines, for example, and particularly with sheet cutters. The pressure with which the top roll bears on the bottom roll is determined by the weight of the top roll and the force exerted by the actuator. Depending on the direction and magnitude of the force exerted by the actuator, the bearing pressure may be set to be greater than, equal to or smaller than the contact pressure due to the weight of the top roll. The actuator normally takes the form of a hydraulically or pneumatically operated cylinder-piston arrangement. With such an actuator, the direction and magnitude of the force can readily be adjusted. However, the use of feed sections employing such cylinder-piston arrangements as actuators is restricted to sites where compressed air or hydraulic oil is available.